This invention relates to a method and apparatus for tinting yarn and, more particularly, to a method and apparatus for applying a fugitive tint to a yarn to identify the yarn.
Generally, an end user, such as a carpet manufacturer, may receive from a yarn producer different types of yarn, having different dyeabilities, tenacities or other properties. Conventionally, the type of yarn is indicated on each package of yarn received from the yarn producer, but when the yarn is removed from the package, it is often impossible for the end user to distinguish it from other types of yarn. This is especially a problem in such processes as twisting, tufting, and mending where several packages of yarn may be used.
Fugitive tints, such as water-soluble dyes have been applied to yarns to enable the type of yarn to be identified by end users. Versatint* N-6 dye (Milliken Laboratories - USA) is normally used on nylon staple while Versatint II dye is recommended for BCF nylon yarns. Other commercially available fugative tints include Megatint* dye (Chemurgy Products Inc). Such tints are removable from the yarn prior to the final processing steps so that product quality is not adversely affected. Attempts have been made to apply such tint to yarn by spraying it onto yarn packages. This has the disadvantage of being messy and environmentally hazardous due to the presence of excess air-borne tint. Moreover, the visibility of the tint along the threadline is low once the yarn is removed from the package and after such operations as twisting, the tint is even more difficult to see. FNT * denotes Trademark